Dissertações em Engenharia de Processos (Mestrado) - PPGEP/ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/10053

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Acesso aberto (Open Access)
Implantação do lean manufacturing na gestão de manutenção no terminal portuário ponta da madeira – TPPM: estudo de caso nos processos de planejamento, programação e controle (PPCM)
(Universidade Federal do Pará, 2021-09-02) FERREIRA, Maryclea Mourão Furtado; BRAGA, Eduardo de Magalhães; http://lattes.cnpq.br/4783553888547500
Na atualidade, estas demandas foram ampliadas e, além de custo, qualidade, velocidade de entrega e flexibilidade, identifica-se um mercado que passa a cobrar pela redução dos impactos ambientais gerados pelos produtos e processos. Tendo como problema os fatores que ocasionam a perda de estabilidade, pode-se elencar as falhas ou quebras dos equipamentos operacionais e estes podem vir a decorrer por vários motivos. Com o objetivo geral de aplicar ferramentas do Lean em um processo de PPCM. Essa pesquisa adotou o estudo de caso para seu desenvolvimento, o estudo de caso indica princípios e regras que devem ser observados durante o processo de investigação. Os resultados principais alcançados foram: o aumento de 5 pontos percentuais (pp) correspondente a 7% na disponibilidade física dos ativos e de 4pp corresponde a 5% na disponibilidade intrínseca, além de ganhos nos indicadores de processos, com aumento de 37pp equivalente a 77% para aderência as manutenções sistemáticas e 37pp equivalente a 25% no indicador de aderência a programação, o que demonstram a eficiência do modelo proposto. Comprovando a importância da aplicação do pensamento enxuto por meio da melhora de alguns indicadores selecionados e consequentemente melhoria nos processos de manutenção.
Acesso aberto (Open Access)
Software para otimizar o processo de análise de não conformidades do sinal de TV digital no padrão SBTVD
(Universidade Federal do Pará, 2022-10-28) NASCIMENTO JUNIOR, Osório Ferreira do; MACEDO, Emanuel Negrão; Emanuel Negrão; SOUZA, Alan Marcel Fernandes de; http://lattes.cnpq.br/6749896733643775; https://orcid.org/0000-0002-1656-5714
An important challenge is applying a methodology capable of creating advanced TV beam validations. Simply checking the beam's binary values, while able to identify many problems, could not identify all types of errors. In addition to this type of verification, there are several possibilities for errors generated during multiplexing, for example errors such as inconsistencies when crossing information between different tables, errors due to the order or frequency in which some tables are transmitted, and errors in synchrony and time data are complex cases that can be identified automatically. To perform the verification of the TV beam, an automation method will be developed that will receive the content transmitted by the broadcaster as input and will execute several algorithms to compare the received data with the expected values defined by the Brazilian Digital TV standard. After comparison the algorithm will notify if the beam is in disagreement with the expected one and will inform you which problems were encountered. The resulting solution should be used by product engineering teams when analyzing problems in the field. In several situations where there are errors in the reception of TV signals, it is necessary to capture the transmitted signals and thoroughly investigate the data, checking each table of the beam. The system will automate and facilitate this operation.
Acesso aberto (Open Access)
AmPA (Amazônia Pale Ale) desenvolvimento tecnológico de cerveja com levedura selvagem amazônicas
(Universidade Federal do Pará, 2022-06-26) AMARAL, Israel Nazareno Athayde do; QUARESMA, Sil Franciley dos Santos; http://lattes.cnpq.br/6860112313500088
Believing in the great potential of the North region of Brazil, we started a research project that highlighted the Amazonian raw material, in this context, for beer production. Amazônia Pale Ale (AmPA) was conceived as a light and refreshing beer, with low bitterness, having as its differential the wild Amazonian yeast. The basic formulation started with barley malt, hops and a wild yeast isolated from cashew apple, evaluating the physicochemical and sensorial characteristics. Cajuaçu is a native and dispersed species in the Amazon, from Maranhão to Mato Grosso and Guianas. in Pará, specifically in Bragança, widely consumed in the period from January to March, the harvest period. This fruit is used for home production of an alcoholic fermentative mixed drink that takes vodka and honey. We submitted the cashew nectar to various culture media, where we found 38 colonies. All samples were tested until choosing the one with the highest potential. Sample C4 was the strain with the best performance in an isolated test on AGAR, so it was isolated and reproduced for continuation of the process. The must was submitted to the steps of brazing, filtering, boiling, cooling and clarification, followed by the inoculation of C4 yeast. The yeast was submitted to a yield test, and after 72 hours in a fermentation test under constant agitation, in a temperature variation between 20 C to 25 C, it reached several density (all corrected by the temperature x density table), we reached a yield of 46.67%, reaching a maximum alcohol content of 5.51% alcohol or that is, approximately 46.6 g of alcohol obtainedx from 100 g of fermented sugar, representing an efficiency in the fermentation process of 81.27%. These results are consistent with those found in the literature, since according to Hashizume (2001), even under optimal working conditions, the highest yield in alcoholic fermentations does not exceed 48%, and, in the industrial process, the yield is even lower. With the yeast chosen and tested, we go to the production of beer. To propose an Amazonian beer, we need to have a base to give the initial “start”, and what has the face of refreshing and tasty beer, which has the greatest characteristics of our Amazon, so we used what was easily accessible, such as spices and fruits. The yeast of Amazonian origin fit perfectly into the proposed style, therefore, showing all the strength and complexity that was expected. For the production of AmPa, we started with a beer of the similar style that we are looking for, so we characterized a light APA, with few hops, and without any spices, so that we could analyze the behavior of yeast in a craft beer. In addition to all that has been said, it has a more acidic character, and this can be obtained in several ways. The first could be brazing, making a “sour mash” acid brazing). Fermentation took place at 20 °C for 7 days. The beer was aged at 2 °C for 8 days, and then bottled and pasteurized. After the elaboration process, 7 days after the beers were analyzed sensorially. It was concluded that there is a possibility of success in the use of wild Amazonian yeasts for the manufacture of beers, creating a unique characteristic, without the presence of off flavor, thus meeting the demand for new biodiversity products linked to the sustainable valuation of biomes and adding even more plus the brewery guides.
Acesso aberto (Open Access)
Inspeção da ponte Senador Fábio Lucena conforme a ABNT NBR 9.452:2019, na cidade de Manaus-AM, 2021/2022
(Universidade Federal do Pará, 2022-11-01) GOMES, Luiz Feitosa; LOAYZA, Cristhian Ricardo Loayza; http://lattes.cnpq.br/4162763961640575; https://orcid.org/0000-0002-0662-715X; BRAGA, Eduardo de Magalhães; http://lattes.cnpq.br/4783553888547500; https://orcid.org/0000-0003-0739-7592
This dissertation covers a case study referring to the ―Inspection of the Senador Fábio Lucena bridge, according to ABNT NBR 9452:2019, located between the neighborhoods of São Raimundo and N. S. Aparecida, in the city of Manaus-AM, 2021/2022 – Analysis of the manifestations pathological‖, with qualitative research, supported by a theoretical framework and field work, with a Study Script, which guided the recording of knowledge and images/photos. The methodological path was based on compliance with current standards and technical specifications. The research content has a general approach on bridges, with emphasis on their pathologies, mainly on their structures, encompassing infrastructure, mesostructure and superstructure, and a brief note on bridges in Brazil, with emphasis on the studied bridge. The results and methods are supported by theoretical study and also by field practice carried out at the investigation site. The research allowed us to infer that this special work of art (OAE), Senador Fábio Lucena bridge, inaugurated in 1987, even with the weather and nature, resulting from the high temperature and humidity typical of the hot and humid equatorial climate of the Region North of the country, and according to its apparent state of conservation, and according to ABNT NBR 9452:2019, it was classified as REGULAR, therefore, lacking periodic maintenance, in medium-term actions, to guarantee good conditions for vehicle traffic and of peop
Acesso aberto (Open Access)
Análise dos impactos financeiros dos serviços de impressão por outsourcing em compras governamentais
(Universidade Federal do Pará, 2022-06-24) XAVIER, Sandra Maria Lima; VIEGAS, Bruno Marques; http://lattes.cnpq.br/1196600058247902
This work aims to evaluate the financial impacts in the provision of printing service comparing the traditional methods, managed by the institution itself, and by outsourcing of printing. The print outsourcing service model has replaced the traditional model with own resources in many public and private agencies. For this study, data from a project for the acquisition of outsourcing services were used to replace the services provided by the government institution itself, so that it was possible to make a comparison between the two models: the traditional one, with the entity's own resources, and the print outsourcing. Comparisons were made through the economic analysis of the costs presented by the bidding companies, as well as the costs of the public institution. Tools were used to analyze the cost/volume/profit from the contribution margin, break-even point and operating leverage, which led to a single decision-making model, the contribution margin. After analyzing the documents related to the costs of printing services by the traditional method and by outsourcing, this study found that the outsourcing of printing is a more economical service than the traditional model, as it ensures an advantage of 130% in relation to the offer.
Acesso aberto (Open Access)
Aplicação de técnicas bayesianas no processo debiolixiviação de urânio
(Universidade Federal do Pará, 2022-04-01) CARDOSO, Altair Costa; ESTUMANO, Diego Cardoso; http://lattes.cnpq.br/5521162828533153; VIEGAS, Bruno Marques; http://lattes.cnpq.br/1196600058247902
This work aims to study the application of Bayesian techniques, Monte Carlo methodvia Markov chain and the importance sampling filter and sequential resampling, for the estimation of kinetic parameters and state variables of the uranium bioleaching processby Acidithiobacillus ferrooxidans. To make the estimates, experimental measures of cell concentration, uranium, ferrous and ferric ion, available in the literature, were used,which were evaluated using a mathematical model composed of a system of ordinary differential equation. Different case studies were conducted involving the measurement and model deviation (1 and 5%), as well as the kinetic model of the specific speed of cell growth. The results of the estimates showed a good agreement with the experimental measurements, presenting coefficient of determination values ranging from 0.95 to 0.99. The mathematical models evaluated were validated by reproducing the experimental measures and the use of Bayesian techniques proved to be adequate.
Acesso aberto (Open Access)
Implantação do sistema milk run em uma empresa do polo de duas rodas em Manaus
(Universidade Federal do Pará, 2022-03-25) NOGUEIRA, Shelle Pontes; ESTUMANO, Diego Cardoso; http://lattes.cnpq.br/5521162828533153
Considering the current situation of the global economic crisis and globalized competition, it is necessary to reduce cost and improve productivity in industrial activities. In this context, logistics in general stands out as a source of opportunity for organizations to establish competitive advantages. In this respect, the present work seeks to highlight the contributions that the Milk Run System can bring to the improvement of the flow of materials in the supply area and with the work in partnership with its suppliers, allowing cost reduction through changes in logistics operations. The work was developed in a multinational company manufacturer of electronic parts for the 2 and 4 wheel poles, located in thecity of Manaus. The study showed that by replacing the conventional system with the Milk Run system, the company is able to improve delivery rates. In the case study, the work was carried out in the four suppliers with the highest volume of cargo, in which it was creating routes and delivery times that best met the interests of the company and suppliers.
Acesso aberto (Open Access)
Otimização do processo de estoque de uma empresa multinacional do polo industrial de Manaus utilizando a ferramneta de análise SWOT
(Universidade Federal do Pará, 2022-04-28) LIMA, Marlen de Araújo; MAGALHÃES, Edilson Marques; http://lattes.cnpq.br/1570353513360972
This work aims to use the SWOT matrix for the optimization of logistics processes, to achieve these objectives, qualitative analyzes were used through data collection according to the steps measured in this work. Constantly understanding the variables and implications of the business scenario leads us to propose a complete mapping of the current situation of the organization, raising the points of non-compliance that affect the business result. The organization's raw material stock, where the high rate of stopped material was identified through the SWOT methodology, Identifying loss indicators and proposing improvements to optimize this process in the organization leads us to understand that large organizations still do not apply a tool for analysis let their income fall, thus affecting profitability, as the stock of a manufacturing company represents about 80% of operating costs, so from this research we have as a result when analyzing data provided, that the stock of stopped material, without use and without control to meet customer demand represents about 5% of financial loss. In this way, we came to the conclusion that the SWOT analysis helped to optimize processes and implement continuous improvements that add gains to the organization
Acesso aberto (Open Access)
Estudo da geração de energia elétrica através dos sistemas fotovoltaicos off-grid.
(Universidade Federal do Pará, 2022-03-21) COLARES, Marcus Valério de Rezende; LEITE, Jandecy Cabral; http://lattes.cnpq.br/7279183940171317
The present work has as objectives the study of the generation of electric energy through the source of solar energy and presents a study on the photovoltaic systems OFF-Grid, systems not connected to the electric grid, respectively. Therefore, this work presents an analysis of OFF-Grid photovoltaic systems. In terms of analyses, it is worth noting that these were carried out from the technical and socio-environmental perspectives, so that, in the first, the OFF-Grid photovoltaic systems themselves are evaluated. In the second, the market demand, Brazilian potential for photovoltaic solar energy generation, the socio-environmental impact, sustainability, as well as the main incentives in Brazil regarding photovoltaic systems are evaluated. The relevance of this work is therefore due to the fact that there is instability in the price of electricity tariffs and due to the high emissions of carbon dioxide, which affect the climate and ecosystems of the planet. In this context, it is necessary to use technologies for the benefit of society, such as photovoltaic solar energy, with the purpose of developing the economy through clean and renewable energy, through the implementation of environmental sustainability practices. As an analysis, the study presents the advantages and disadvantages of the aforementioned system. Thus, the analyzes presented in this study show that the implementation of photovoltaic systems is a great alternative to reduce environmental impacts and diversify the energy matrix.
Acesso aberto (Open Access)
Implementação do lean manufacturing em uma oficina de recuperação de componentes localizada em uma empresa do setor de mineração - São Luís - MA
(Universidade Federal do Pará, 2022-01-28) MENDES, Claudia Gonçalves; BATISTA, Clauderino da Silva; http://lattes.cnpq.br/1345689043203622
The success of a company in a competitive and globalized market is in the ability to identify and eliminate waste, reduce costs, add value to the customer, stabilize, innovate and continuously improve its processes. This justifies the performance of work in which with the growing scarcity of resources and the need to improve maintenance processes, it is sought to plan and improve activities in order to obtain a quality product satisfying the company's customers and employees, the more efficient is the planning and scheduling of maintenance, the lower the rates of rework and unscheduled maintenance. The objectives demonstrate the application of Lean Manufacturing tools in a Component Recovery Workshop located at the Ponta da Madeira Port Terminal -TPPM in São Luís in Maranhão. Among the methodologies addressed, this research has a qualitative character because it is centered on the reality of the company, in addition to being bibliographic, documentary because existing data are used, the data collected are predominantly descriptive, the researcher's interest when studying a particular problem is to verify how it manifests itself in daily activities, procedures and interactions, data analysis tends to follow an inductive process. The results obtained thus evidencing continuous improvement works aimed at operational excellence, training of several teams in various processes, elimination of waste and results aimed at financial gain. There were also defenses of new investments for the Workshop with new technologies positively impacting productivity
Acesso aberto (Open Access)
Indicadores de alcance das expectativas do projeto industrial na zona franca de Manaus a partir do processo de acompanhamento das contrapartidas obrigatórias
(Universidade Federal do Pará, 2022-06-03) SENA, José Roberto Carvalho; MAGNO, Rui Nelson Otoni; http://lattes.cnpq.br/9017163598972975
The work in question details the process of granting, implementing and monitoring the industrial project and, based on the data collected resulting from the sample selected between the years 2017 to 2020, built indicators of reaching the expectations of the approved industrial project that can structure the flow inspection and analysis of the results of the tax waiver granted. The study used quantitative methods to determine technical, documentary and bibliographic procedures of the Superintendence of the Free Trade Zone of Manaus (SUFRAMA). Data collection was intended to be descriptive and exploratory, in order to carry out a statistical analysis of the results and an interrelationship between the indicators in order to determine which levelers are aligned with the effectiveness of the public policy that brings improvements and development to the region, with regard to the Manaus Free Trade Zone. Six (6) indicators were created to quantitatively measure the data of the planned project versus the one carried out. With the study it was observed that the effectiveness of the implementation of the industrial project in the Industrial Pole of Manaus - PIM, from the point of life of the counterpart expectation X reality measured and analyzed, depends on factors often inherent to the decisions of companies and it is noticed that neither all companies were able to comply, and it may have been the fact of oversizing the data in the project. Without going into detail, the pandemic did not have a significant impact as initially planned. Corroborating this way, with the positive results obtained by the companies implanted/studied in the Industrial Pole of Manaus.
Acesso aberto (Open Access)
Método para monitoramento de desempenho em tempo real e a cadeia de ajuda como apoio a estratégia da manufatura enxuta
(Universidade Federal do Pará, 2022-02-22) SANTOS, Tamires Priscila Souza dos; LEITE, Jandecy Cabral; http://lattes.cnpq.br/7279183940171317
With the advancement of technologies, the market increasingly drives competitiveness, where new performance standards are imposed, generating a series of challenges for companies, such as the need for paradigm shifts in relation to many things, but mainly productive process control. The rapid absorption of external elements, new projects, rotating teams, demand fluctuation and other variables, makes companies to create and innovate mechanisms to adapt themselves and apply quick respond to the findings and issues. The survival key for any production process is low cost and high quality. To meet this expectation, online controls are implemented to block manufacturing issues that can go out of control if not detected on time. The Lean Manufacturing strategy has helped in thisbattle, however, some of the proposed tools, such as production control methods based on self-control by the operators themselves, in general employing management boards in sight at the workstations, are often not enough to ensure the accuracy of information to identify the root causes of problems in companies where the practice of continuous improvement by problem identification, analysis and solution is not as strong. This work proposes a method of implementing real-time production performance monitoring within the Lean Manufacturing strategy that, with the creation of a Help Chain, that when effectively triggered by an online system, drives the rapid solution of problems. Real-time monitoring of production performance creates favorable conditions for verifying the effectiveness of any improvement implemented and for permanently monitoring the results. The case study of the implementation of the proposed method of monitoring the real-time performance of manufacturing of a company in the electronics industry will be reported.
Acesso aberto (Open Access)
Implantação da ferramenta BI no sistema de inteligência de negócios para tomadas de decisões no processo produtivo da empresa Makauta em Manaus
(Universidade Federal do Pará, 2022-02-22) CAVALCANTE, Luiz Carlos Monteiro; LEITE, Jandecy Cabral; http://lattes.cnpq.br/7279183940171317
The evolution of the production process, formerly "shop floor", has been significant in recent decades. Many projects have been developed for the deployment of ―industry 4.0‖. Major investments have been made in infrastructure, automation, training and information systems, making this sector a strategic area in a timely manner for companies. ―Shop floor‖ today generates a large amount of data that, because it is scattered or disorganized, is not used to its full potential as a source of information for decision making. Thinking about this under-utilization of the information provided in the production process, this paper proposes the implementation of a Business Intelligence system through the use of the Qlik Sense tool, applied specifically to the treatment of ―shop floor‖ data. The goal is to develop a system that uses the data resulting from the production process and transforms it into information that helps managers make timely decisions in this process in order to improve the company's competitiveness.
Acesso aberto (Open Access)
Otimização da confiabilidade e usabilidade de testes funcionais de processo produtivo na empresa “tucumã sem casca” de cable modems do pólo industrial de Manaus
(Universidade Federal do Pará, 2022-03-21) BARBOSA FILHO, Geraldo Freitas; LEITE, Jandecy Cabral; http://lattes.cnpq.br/7279183940171317
The jig equipment responsible for the function tests are complex and highly capable machines used in the electronics industry to validate the functionality of analogic and digital devices or any other product of electronic factories of the industry pole of Manaus. In the studied process, those machines are operated in a series configuration, and the effect of a failure in this type of configuration is very critical, as the simplest failure can impact the production process and generate losses for the company. This work aims to assess the behavior of test equipment in a cable modem and set top box production processes, to make analysis of the failures happened during this production process, to guide a reliability study that enable the maintenance manager to make decisions about how to deal with equipment aiming to reduce failure rates and use proper maintenance practices to allow reliability to be maximized
Acesso aberto (Open Access)
Modelos de estimativa de radiação solar global e análise Estatística em dez cidades do Estado do Pará – Brasil
(Universidade Federal do Pará, 2022-01-28) VALENTE, Alexandre Miguel da Cruz; ESTUMANO, Diego Cardoso; http://lattes.cnpq.br/5521162828533153
Estimating solar radiation is important for various segments of society such as agriculture, meteorology and electricity generation (photovoltaic systems). This workaims to estimate the Global Solar Radiation in ten cities in the state of Pará - Brazil, using estimation models, Hargreaves-Samani and Bristow-Campbell, using meteorological data provided by Automatic Meteorological Stations, belonging to the National Institute of Meteorology (INMET), to compare the observed and estimated values and analyze which model best fits the region, through the parameters Coefficient of Determination (R²), Willmott Index (d), Pearson correlation coefficient (r) andRelative Root Mean Squared Error (rRMSE). The results showed that the models are satisfactory and can be used to estimate the Global Solar Radiation, however for the less rainy period there was an overestimation, between june and november. The Castanhal station had the lowest average global solar radiation compared to the other stations with an average daily radiation equal to 15.06 M/m².day, while the city of Redenção had the highest daily average, 18.33 MJ /m².day. The city of Tomé Açu presented better fit of the models referring to the observed values, since for the HS model, the confidence index was considered very good, c equal to 0.78, and the relative RMSE was considered excellent, with rRMSE equal to 9.93%. For the B-C model for this station, the confidence index and the relative RMSE were considered good, c equal to 0.71 and rRMSE equal to 19.14%.
Acesso aberto (Open Access)
Aplicação de software estatístico na prática de ensino em ciência da educação
(Universidade Federal do Pará, 2022-02-16) SILVA, Sarley de Araújo; MAGNO, Rui Nelson Otoni; http://lattes.cnpq.br/9017163598972975
The CEP provides the quality control of an institution's engineering applications, that is, in the choice of questions and analysis of variables. This control makes use of statistical tools for continuous process improvement. In view of this, the present work aimed to control abnormalities in probability and statistics problems through the use of control charts from the Minitab Software, specifically, the implementation of the concepts of control charts by variables and attributes was sought. To carry out this theme, the quantitative methodology and the control chart of the Minitab Software were used. The results obtained in the graphs presented during this study allowed us to identify, correct and reduce variations in statistical problems, providing clear and precise solutions to the most complex issues. It is concluded that the use of the software brings improvement in applications of the statistical sciences, it becomes important for solving problems in several areas, since the issues analyzed by this method reduce the variability, achieving results with greater precision. Thus, the statistical tool from the charts and their corrective actions is capable of stabilizing the standard deviations and improving the specific standard of the applications proposed in the teaching of educational science
Acesso aberto (Open Access)
Um modelo de previsão de vendas em uma empresa de médio porte na cidade de Manaus
(Universidade Federal do Pará, 2022-02-18) FONSECA, Vera Lúcia de Assis da Fonseca; MAGNO, Rui Nelson Otoni; http://lattes.cnpq.br/9017163598972975
The sales forecasting process has been structured over time with new technologies and tools, for data consolidation and handling. The companies, which previously had no focus on the sales forecasting process, were not impacted by the lack of it, but currently, adjustments are necessary for its insertion, because there is consensus that only intuitivity, usually directed by past experiences or subjectivities, or optimized results or underestimated them. Walking in the above, this research aims to identify a sales forecast model appropriate to the portfolio of a medium-sized beverage company. In the study of this dissertation, the explanatory research technique was applied with exploratory and descriptive analyses, and minitab® and Excel software was also used® to perform the analyses through statistical abstracts, tables and figures, so that there was the assertive choice of the model to be applied to the business. Qualitative and quantitative forecastmodels, graphic analysis, residue scans and forecast error calculations were evaluated. The mean deviations and MAPEs (Mean Absolute Percent Error) of the models were compared: moving average, exponential smoothing, linear trend and holt winter and, as conclusion, the models with the lowest prediction errors were: moving average N=2 with MAPE=14.8%, exponential smoothing with MAPE=15.2% and linear trend with MAPE=15.4%. The choice was for the exponential smoothing model, although not the slightest error is easy to apply and weights the historical data.
Acesso aberto (Open Access)
Estimativa de parâmetros aplicados em modelos epidemiológicos
(Universidade Federal do Pará, 2022-01-28) PINTO, Thiago Moreira; ESTUMANO, Diego Cardoso; http://lattes.cnpq.br/5521162828533153
In this study, the Bayesian Monte Carlo technique via Markov Chain (MCMC) was selected to estimate the parameters of the differential equations of the SQUIDER3 and SEIR4 compartmental models, seeking to reflect the propagation of Covid-19 in the state of Pará. An algorithm was developed in Matlab, reproducing the MCMC technique that uses stochastic processes and simulates a random selection of values of each parameter. When sampling proportionally to the probability of the values, a probability distribution was reached in order to be able to both adjust the model parameters and converge to the stationary distribution of interest. The parameters estimated in this paper for the SQUIDER and SEIR compartmental models were compared to real data using the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) metrics. Both of these were applied for a better definition of the model that best represents the Covid-19 propagation phenomenon in the state of Pará. As a result, histograms were obtained that indicate a convergence of parameters in the SQUIDER model, which did not happen in the SEIR model. By applying the AIC and BIC, it was demonstrated that the SQUIDER model was the best model to represent the phenomena (i.e. the propagation of Covid-19 in the state of Pará), and has the potential to be used as a predictive model.
Acesso aberto (Open Access)
O Uso da lógica fuzzy no auxílio da gestão e controle dos níveis de estoques de peças
(Universidade Federal do Pará, 2021-09-30) MACIEL, Gerberson das Chagas gomes; FERREIRA, Josiel Lobato; http://lattes.cnpq.br/0187722217624180; https://orcid.org/0000-0003-0345-3526
Faced with a highly competitive scenario, this study aims to develop a tool that analyzes the stocks based on fuzzy logic inferences, when the output variable is the stock level and the customer demand and the production plan are the input variables. Providing the companies a better management of their stock levels. In addition to ensuring an efficient production system and optimizing the occupation of locations in the finished product stock. Through this research, the stock level analyzes were performed using the fuzzy toolbox of the Matlab software version 2015a, in models of a product aimed at the automotive segment, manufactured by a company from the Industrial Pole of Manaus. After the analysis, several situations as excess and lack of parts in stock were identified, in addition to large variations in the production plan. After applying the analysis tool, the normal level of stock rose from 20% to 93%, the excess rate and the risk of delivery failures were eliminated, as well as the variation in the production plan. These results allowed the validation of the tool's effectiveness, which proved to be applicable in any type of stock, in any type of company.
Acesso aberto (Open Access)
Alocação de religadores automáticos em uma subestação de energia elétrica
(Universidade Federal do Pará, 2021-09-17) NASCIMENTO, Osório Ferreira do; VIEGAS, Bruno Marques; http://lattes.cnpq.br/1196600058247902
This work aims to reduce the number of damaged reclosers and evaluate the electric power distribution process in a 69 kV substation in the city of Manaus. To achieve the objective, the allocation of reclosers was evaluated, with installation at the outputs of 13.8 kV buses, with a descriptive methodology, based on a technical literature study with specifications of equipment and substation techniques, in addition to of national and international normative standards from a construction standard of a 69 kV substation. It was found that the energized and de-energized devices performed as expected, demonstrating the possibility of adapting the reclosers to the 13.8 kV bars, operating satisfactorily within the estimated times for implementation in field equipment and commissioning with the system. Using the recloser allocation, the number of disconnections was reduced by 95.1% and the disconnection time by 94.4%. With the application of the payoff method, using the quantity of disconnections of two circuit breakers during the year 2018 and the amount spent by the company in moving a team to resolve the situation of accidental disconnections, a profit of BRL 62,252 was obtained .87 due to savings over 5 years.